Many members, such as the lids of make-up boxes, washing machines or automotive vehicle glove compartments, have their opening actuated, for example by springs, or are brought to the open position under the effect of gravity.
In practice, a rotation-retarding device is thus generally implemented to give smooth, dampened opening of the lid.
According to an arrangement already known, a viscous fluid, such as a silicone oil, is used to retard the rotation of a rotor with respect to a stator by virtue of its viscosity. This type of rotation-retarding device does not enable sufficient couples to be produced in a compact space, such as that available for a hinge of a make-up box.
According to another arrangement already known, the rotation-retarding device is obtained by deformation of elastically deformable flexible material. These friction-based rotation-retarding devices give a constant couple which does not guarantee opening that is complete and of good quality.